# 2as = v^2 an other equations dealing with the past

• I
2as = v^2 but why do they have the formula 2as = v^2-vo^2 displayed as correct with out a reference that its wrong. In Basic physics classes it may not even be mentioned that its wrong. I understand that no one is teaching relativistic physics but why not even mention it. Its been over a 100 years and its still being used in physics books today as being correct along with other formulae dealing with the past.

Staff Emeritus
2019 Award
fresh_42
Mentor
What is your question? Newton's physic is good enough to cover most of all real world problems. As it is easier, it doesn't make sense to calculate the movement of a car relativistic. It's not measurable.
but why not even mention it
It will be mentioned where it is relevant.

If you meant the difference of the term ##v_0##, then this is the difference whether there is an initial velocity before acceleration starts or not. Both are valid for certain cases.

Dale
Mentor
its still being used in physics books today as being correct along with other formulae dealing with the past.
It is still being used because it is still correct within its domain of applicability, as shown by a mountain of experimental evidence.

Edit: actually, the suvat equations are exactly correct, even in relativity.

Last edited: